xref: /openbmc/u-boot/drivers/spi/ti_qspi.c (revision 9fc2ed40)
1 /*
2  * TI QSPI driver
3  *
4  * Copyright (C) 2013, Texas Instruments, Incorporated
5  *
6  * SPDX-License-Identifier: GPL-2.0+
7  */
8 
9 #include <common.h>
10 #include <asm/io.h>
11 #include <asm/arch/omap.h>
12 #include <malloc.h>
13 #include <spi.h>
14 #include <asm/gpio.h>
15 #include <asm/omap_gpio.h>
16 
17 /* ti qpsi register bit masks */
18 #define QSPI_TIMEOUT                    2000000
19 #define QSPI_FCLK                       192000000
20 /* clock control */
21 #define QSPI_CLK_EN                     (1 << 31)
22 #define QSPI_CLK_DIV_MAX                0xffff
23 /* command */
24 #define QSPI_EN_CS(n)                   (n << 28)
25 #define QSPI_WLEN(n)                    ((n-1) << 19)
26 #define QSPI_3_PIN                      (1 << 18)
27 #define QSPI_RD_SNGL                    (1 << 16)
28 #define QSPI_WR_SNGL                    (2 << 16)
29 #define QSPI_INVAL                      (4 << 16)
30 #define QSPI_RD_QUAD                    (7 << 16)
31 /* device control */
32 #define QSPI_DD(m, n)                   (m << (3 + n*8))
33 #define QSPI_CKPHA(n)                   (1 << (2 + n*8))
34 #define QSPI_CSPOL(n)                   (1 << (1 + n*8))
35 #define QSPI_CKPOL(n)                   (1 << (n*8))
36 /* status */
37 #define QSPI_WC                         (1 << 1)
38 #define QSPI_BUSY                       (1 << 0)
39 #define QSPI_WC_BUSY                    (QSPI_WC | QSPI_BUSY)
40 #define QSPI_XFER_DONE                  QSPI_WC
41 #define MM_SWITCH                       0x01
42 #define MEM_CS                          0x100
43 #define MEM_CS_UNSELECT                 0xfffff0ff
44 #define MMAP_START_ADDR_DRA		0x5c000000
45 #define MMAP_START_ADDR_AM43x		0x30000000
46 #define CORE_CTRL_IO                    0x4a002558
47 
48 #define QSPI_CMD_READ                   (0x3 << 0)
49 #define QSPI_CMD_READ_QUAD              (0x6b << 0)
50 #define QSPI_CMD_READ_FAST              (0x0b << 0)
51 #define QSPI_SETUP0_NUM_A_BYTES         (0x2 << 8)
52 #define QSPI_SETUP0_NUM_D_BYTES_NO_BITS (0x0 << 10)
53 #define QSPI_SETUP0_NUM_D_BYTES_8_BITS  (0x1 << 10)
54 #define QSPI_SETUP0_READ_NORMAL         (0x0 << 12)
55 #define QSPI_SETUP0_READ_QUAD           (0x3 << 12)
56 #define QSPI_CMD_WRITE                  (0x2 << 16)
57 #define QSPI_NUM_DUMMY_BITS             (0x0 << 24)
58 
59 /* ti qspi register set */
60 struct ti_qspi_regs {
61 	u32 pid;
62 	u32 pad0[3];
63 	u32 sysconfig;
64 	u32 pad1[3];
65 	u32 int_stat_raw;
66 	u32 int_stat_en;
67 	u32 int_en_set;
68 	u32 int_en_ctlr;
69 	u32 intc_eoi;
70 	u32 pad2[3];
71 	u32 clk_ctrl;
72 	u32 dc;
73 	u32 cmd;
74 	u32 status;
75 	u32 data;
76 	u32 setup0;
77 	u32 setup1;
78 	u32 setup2;
79 	u32 setup3;
80 	u32 memswitch;
81 	u32 data1;
82 	u32 data2;
83 	u32 data3;
84 };
85 
86 /* ti qspi slave */
87 struct ti_qspi_slave {
88 	struct spi_slave slave;
89 	struct ti_qspi_regs *base;
90 	unsigned int mode;
91 	u32 cmd;
92 	u32 dc;
93 };
94 
95 static inline struct ti_qspi_slave *to_ti_qspi_slave(struct spi_slave *slave)
96 {
97 	return container_of(slave, struct ti_qspi_slave, slave);
98 }
99 
100 static void ti_spi_setup_spi_register(struct ti_qspi_slave *qslave)
101 {
102 	struct spi_slave *slave = &qslave->slave;
103 	u32 memval = 0;
104 
105 #ifdef CONFIG_DRA7XX
106 	slave->memory_map = (void *)MMAP_START_ADDR_DRA;
107 #else
108 	slave->memory_map = (void *)MMAP_START_ADDR_AM43x;
109 #endif
110 
111 	memval |= QSPI_CMD_READ | QSPI_SETUP0_NUM_A_BYTES |
112 			QSPI_SETUP0_NUM_D_BYTES_NO_BITS |
113 			QSPI_SETUP0_READ_NORMAL | QSPI_CMD_WRITE |
114 			QSPI_NUM_DUMMY_BITS;
115 
116 	writel(memval, &qslave->base->setup0);
117 }
118 
119 static void ti_spi_set_speed(struct spi_slave *slave, uint hz)
120 {
121 	struct ti_qspi_slave *qslave = to_ti_qspi_slave(slave);
122 	uint clk_div;
123 
124 	debug("ti_spi_set_speed: hz: %d, clock divider %d\n", hz, clk_div);
125 
126 	if (!hz)
127 		clk_div = 0;
128 	else
129 		clk_div = (QSPI_FCLK / hz) - 1;
130 
131 	/* disable SCLK */
132 	writel(readl(&qslave->base->clk_ctrl) & ~QSPI_CLK_EN,
133 	       &qslave->base->clk_ctrl);
134 
135 	/* assign clk_div values */
136 	if (clk_div < 0)
137 		clk_div = 0;
138 	else if (clk_div > QSPI_CLK_DIV_MAX)
139 		clk_div = QSPI_CLK_DIV_MAX;
140 
141 	/* enable SCLK */
142 	writel(QSPI_CLK_EN | clk_div, &qslave->base->clk_ctrl);
143 }
144 
145 int spi_cs_is_valid(unsigned int bus, unsigned int cs)
146 {
147 	return 1;
148 }
149 
150 void spi_cs_activate(struct spi_slave *slave)
151 {
152 	/* CS handled in xfer */
153 	return;
154 }
155 
156 void spi_cs_deactivate(struct spi_slave *slave)
157 {
158 	struct ti_qspi_slave *qslave = to_ti_qspi_slave(slave);
159 
160 	debug("spi_cs_deactivate: 0x%08x\n", (u32)slave);
161 
162 	writel(qslave->cmd | QSPI_INVAL, &qslave->base->cmd);
163 }
164 
165 void spi_init(void)
166 {
167 	/* nothing to do */
168 }
169 
170 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
171 				  unsigned int max_hz, unsigned int mode)
172 {
173 	struct ti_qspi_slave *qslave;
174 
175 #ifdef CONFIG_AM43XX
176 	gpio_request(CONFIG_QSPI_SEL_GPIO, "qspi_gpio");
177 	gpio_direction_output(CONFIG_QSPI_SEL_GPIO, 1);
178 #endif
179 
180 	qslave = spi_alloc_slave(struct ti_qspi_slave, bus, cs);
181 	if (!qslave) {
182 		printf("SPI_error: Fail to allocate ti_qspi_slave\n");
183 		return NULL;
184 	}
185 
186 	qslave->base = (struct ti_qspi_regs *)QSPI_BASE;
187 	qslave->mode = mode;
188 
189 	ti_spi_set_speed(&qslave->slave, max_hz);
190 
191 #ifdef CONFIG_TI_SPI_MMAP
192 	ti_spi_setup_spi_register(qslave);
193 #endif
194 
195 	return &qslave->slave;
196 }
197 
198 void spi_free_slave(struct spi_slave *slave)
199 {
200 	struct ti_qspi_slave *qslave = to_ti_qspi_slave(slave);
201 	free(qslave);
202 }
203 
204 int spi_claim_bus(struct spi_slave *slave)
205 {
206 	struct ti_qspi_slave *qslave = to_ti_qspi_slave(slave);
207 
208 	debug("spi_claim_bus: bus:%i cs:%i\n", slave->bus, slave->cs);
209 
210 	qslave->dc = 0;
211 	if (qslave->mode & SPI_CPHA)
212 		qslave->dc |= QSPI_CKPHA(slave->cs);
213 	if (qslave->mode & SPI_CPOL)
214 		qslave->dc |= QSPI_CKPOL(slave->cs);
215 	if (qslave->mode & SPI_CS_HIGH)
216 		qslave->dc |= QSPI_CSPOL(slave->cs);
217 
218 	writel(qslave->dc, &qslave->base->dc);
219 	writel(0, &qslave->base->cmd);
220 	writel(0, &qslave->base->data);
221 
222 	return 0;
223 }
224 
225 void spi_release_bus(struct spi_slave *slave)
226 {
227 	struct ti_qspi_slave *qslave = to_ti_qspi_slave(slave);
228 
229 	debug("spi_release_bus: bus:%i cs:%i\n", slave->bus, slave->cs);
230 
231 	writel(0, &qslave->base->dc);
232 	writel(0, &qslave->base->cmd);
233 	writel(0, &qslave->base->data);
234 }
235 
236 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
237 	     void *din, unsigned long flags)
238 {
239 	struct ti_qspi_slave *qslave = to_ti_qspi_slave(slave);
240 	uint words = bitlen >> 3; /* fixed 8-bit word length */
241 	const uchar *txp = dout;
242 	uchar *rxp = din;
243 	uint status;
244 	int timeout;
245 
246 #ifdef CONFIG_DRA7XX
247 	int val;
248 #endif
249 
250 	debug("spi_xfer: bus:%i cs:%i bitlen:%i words:%i flags:%lx\n",
251 	      slave->bus, slave->cs, bitlen, words, flags);
252 
253 	/* Setup mmap flags */
254 	if (flags & SPI_XFER_MMAP) {
255 		writel(MM_SWITCH, &qslave->base->memswitch);
256 #ifdef CONFIG_DRA7XX
257 		val = readl(CORE_CTRL_IO);
258 		val |= MEM_CS;
259 		writel(val, CORE_CTRL_IO);
260 #endif
261 		return 0;
262 	} else if (flags & SPI_XFER_MMAP_END) {
263 		writel(~MM_SWITCH, &qslave->base->memswitch);
264 #ifdef CONFIG_DRA7XX
265 		val = readl(CORE_CTRL_IO);
266 		val &= MEM_CS_UNSELECT;
267 		writel(val, CORE_CTRL_IO);
268 #endif
269 		return 0;
270 	}
271 
272 	if (bitlen == 0)
273 		return -1;
274 
275 	if (bitlen % 8) {
276 		debug("spi_xfer: Non byte aligned SPI transfer\n");
277 		return -1;
278 	}
279 
280 	/* Setup command reg */
281 	qslave->cmd = 0;
282 	qslave->cmd |= QSPI_WLEN(8);
283 	qslave->cmd |= QSPI_EN_CS(slave->cs);
284 	if (flags & SPI_3WIRE)
285 		qslave->cmd |= QSPI_3_PIN;
286 	qslave->cmd |= 0xfff;
287 
288 /* FIXME: This delay is required for successfull
289  * completion of read/write/erase. Once its root
290  * caused, it will be remove from the driver.
291  */
292 #ifdef CONFIG_AM43XX
293 	udelay(100);
294 #endif
295 	while (words--) {
296 		if (txp) {
297 			debug("tx cmd %08x dc %08x data %02x\n",
298 			      qslave->cmd | QSPI_WR_SNGL, qslave->dc, *txp);
299 			writel(*txp++, &qslave->base->data);
300 			writel(qslave->cmd | QSPI_WR_SNGL,
301 			       &qslave->base->cmd);
302 			status = readl(&qslave->base->status);
303 			timeout = QSPI_TIMEOUT;
304 			while ((status & QSPI_WC_BUSY) != QSPI_XFER_DONE) {
305 				if (--timeout < 0) {
306 					printf("spi_xfer: TX timeout!\n");
307 					return -1;
308 				}
309 				status = readl(&qslave->base->status);
310 			}
311 			debug("tx done, status %08x\n", status);
312 		}
313 		if (rxp) {
314 			qslave->cmd |= QSPI_RD_SNGL;
315 			debug("rx cmd %08x dc %08x\n",
316 			      qslave->cmd, qslave->dc);
317 			#ifdef CONFIG_DRA7XX
318 				udelay(500);
319 			#endif
320 			writel(qslave->cmd, &qslave->base->cmd);
321 			status = readl(&qslave->base->status);
322 			timeout = QSPI_TIMEOUT;
323 			while ((status & QSPI_WC_BUSY) != QSPI_XFER_DONE) {
324 				if (--timeout < 0) {
325 					printf("spi_xfer: RX timeout!\n");
326 					return -1;
327 				}
328 				status = readl(&qslave->base->status);
329 			}
330 			*rxp++ = readl(&qslave->base->data);
331 			debug("rx done, status %08x, read %02x\n",
332 			      status, *(rxp-1));
333 		}
334 	}
335 
336 	/* Terminate frame */
337 	if (flags & SPI_XFER_END)
338 		spi_cs_deactivate(slave);
339 
340 	return 0;
341 }
342